The structure and nanomechanical properties of the adhesive mucilage that mediates diatom-substratum adhesion and motility

Abstract

We investigated the adhesive mucilage and mechanism of cell-substratum adhesion of two benthic raphid diatoms, the marine species Craspedostauros australis E. J. Cox and the freshwater species Pinnularia viridis (Nitzsch) Ehrenberg. SEM images of P. viridis and C. australis cells revealed the presence of multistranded tethers that appear to arise along the raphe openings and extend for a considerable distance from the cell before forming a "holdfast-like" attachment with the substratum. We propose that the tethers result from the elongation/ stretching of composite adhesive mucilage strands secreted from raphes during the onset of cell adhesion and reorientation. Atomic force microscopy (AFM..